I’ve had this purifier for a few days now. I can tell the difference in my apartment by having this purifier. It has helped reduce the cooking smells, helped with my allergies, and dust. 
I have a cat and found out I’m allergic to cats. It has helped reduce my sneezing, itchy eyes and sneezing. Breathing better, as well.
The purifier isn’t loud. The price was reasonable,replacement filters aren’t hard to find and doesn’t cost a fortune.